If your OT is playing OT, then Pulling Lineman is worthless. It only works on run plays (per the description) and Gs are the only O linemen that pull on runs currently.
In no particular order; Pass Blocker, Stonewall, Great Blocker, Showboat Blocker would all be better for an OT depending on his build and team. It doesn't look like he's going to be getting a lot of pancakes outside of blowout wins, so I'd rule out Showboat. Stonewall is good for avoiding reverse pancakes or giving up ground pass blocking but the size of the bonus is small for a non-attribute VA. Your team is struggling pretty badly so Pass Blocker is probably going to activate quite a lot as you face a lot of 2nd and 10+ or 3rd and long passing situations and it offer a 2% bonus to 2 important stats for every point.
